Blood Pressure Sensor – Tech Tips with Vernier

August 28, 2019 0 By Bertrand Dibbert


Hello, I’m John Melville from Vernier Software & Technology, and I’m going to be talking to you today about how to use our blood pressure sensor. Now our blood pressure sensor will give you key certain parameters of blood pressure, such as systolic blood pressure, diastolic pressure, and it will also calculate your MAP, which is your mean arterial pressure, and it will also give you your pulse rate. Now the blood pressure sensor comes with this little sensor, which gets plugged into the LabQuest 2. And it also comes with a cuff that is attached to the blood pressure sensor. The cuff has to be attached to the arm, left or right, and we’re actually going to be measuring little pulses from the brachial artery in the arm to determine those parameters for blood pressure: systolic pressure, diastolic pressure, MAP, and then pulse. Now there’s a few key differences in how this blood pressure sensor works than, say, the way that your blood pressure would be taken if you went to a doctor’s office, and I’ll explain those later. First, I just want to show you how to use the device and get good data with it. The most key thing that you need to remember is once you begin collecting blood pressure data, you need to let the LabQuest just collect and continue to collect, don’t stop collection until it’s done, and then it will actually calculate the parameters for you. So what I’m going to do next is I’m just going to attach the cuff to the blood pressure sensor, plug the blood pressure sensor into the LabQuest, and then attach the cuff to my arm. So I’m going to plug in the blood pressure sensor… attach the cuff to the sensor itself… and then next I’m going to put the cuff on my arm. So now that I’ve placed the blood pressure cuff on my arm, I just want to show you a few things. If I lift this little flap, you can see right here where it says “artery.” Now, this arrow normally should be right over the brachial artery, which is located right around in here. It’s not critical that it’s placed directly over the artery to get good data. You could also get good data if these two tubes are just placed in the crease of the elbow. But I’m just going to place it over here a little bit like that. The most important thing to do when you are collecting blood pressure data is that the subject — that’s me, in this case — can’t move. You have to sit very still and quiet. The other important thing is not to tap on the bulb or tap on the release rate valve or release pressure. You need to just pump up the valve, collect data, and then let the LabQuest finish collecting data so that it can calculate the parameters that you’re interested in. So what I’m going to do next is I’m just going to begin data collection by tapping on the start button, then I’m going to pump the blood pressure cuff up to just over 150, and then I’m just going to let it go, and then the LabQuest 2 will calculate the blood pressure parameters. So over here I’m going to tap then on this “collect” button, and then I will pump up the blood pressure cuff, and then I’m just going to gently put it down and sit quietly for about 100 seconds until the LabQuest 2 finishes collecting data. And I’m going to pump this up. Now I’m going to sit quietly. And now that the blood pressure — the cuff pressure is below 50 millimeters of mercury, I can release the pressure. You can see the pressure drop on the LabQuest screen. So that’s where I released the cuff pressure. But once again, don’t stop data collection. Let the LabQuest continue to collect data. So the LabQuest 2 is finished collecting data, and what we can see right here — I’m just going to scroll down a little bit using these arrow keys. My systolic blood pressure was 134. Now that’s a little bit high, but I run a little bit high, so my blood pressure tends to be a little bit higher than 120. 130 is pretty normal for me. My diastolic pressure is 89, around 90. My pulse was calculated to be at around 70 beats per minute, which is pretty normal for me. And my mean arterial pressure was around 106 millimeters of mercury. So the key things that you need to know about this blood pressure sensor are: one, that the cuff needs to be on tight; that you don’t want to touch the release valve once you’ve pumped it up, or have the subject move; and most importantly, you need to allow the LabQuest to finish collecting data. Don’t hit the stop button before it’s done collecting. Just let the LabQuest collect data. When it’s done collecting data, then it will calculate your blood pressure parameters. If you follow those key things, you should be able to get very good blood pressure data. So for more information about physiology sensors or other Vernier products, please visit our website at www.vernier.com.